Good book. This is a small book of only 200 pages and tells the story of John Harrison, a clock maker. In the early 1700s, and for years before, one of the major scientific problems was the navigation problem of how to determine longitude, or where you were, east/west, on the high seas. With the compass, mariners knew which way was north, and which way was south. By plotting the movement of the sun with a sexton, they could determine how far north or south they were, that is, they could determine you latitude. But there was no way to determine how far east or west you were. This was a serious problem, and many ships were lost with all hands and much treasure was lost simplify because ships got lost at sea.

By the early 1700s, scientists had determined, in theory, that you could determine your longitude if you had an accurate watch set to the time at your home port. If you knew local time, and could compare that with the clock’s time, you could calculate how far east or west you were. The problem was that there were no clocks in the 1700s that were accurate enough or robust enough to work on an ocean vessel. In those days, clock were so inaccurate that they had to be reset each day at noon.

This little book tells the story of John Harrison and his 40 year quest to build a clock accurate enough and robust enough to survive a sea voyage. He had an extremely difficult time because he was self educated, and he was not a clock builder by trade. He was a carpenter by trade, and his first clocks were made entirely of wood. Plus, because he was self-educated, he had a hard time convincing the learned men of the day that he was capable of building such a clock. If the learned men of the day, and the recognized clock-makers of the day could not build such a clock, how would it be possible for a carpenter to build such a device.

But after a lengthy struggle, Harrison’s chronometer because the standard way for determining longitude. It was only recently replaced when GPS became available. I recommend this book. ( )

subtitled *The True Story of a Lone Genius Who Solved the Greatest Scientific Problem of His Time*

Although this book was only 175 pages long, it took me longer than I expected it to, to get through it. This is probably due to the fact that there was much more *math* and mathematical detail than my non-math brain could process and rather than just skim and skip, I tried to get through it all. The story itself, of John Harrison and his valiant attempts at inventing an instrument that would accurately determine longitude, the most pressing scientific challenge of his time, was fascinating. He was treated so badly by the organization which sponsored the competition to award the inventor; it was truly shameful. I guess this aspect of human nature hasn't changed much over time.

There are 2 quotes, one from the beginning of the book, and one from the very end, that I liked:

"...Time is to clock as mind is to brain.. The clock or watch somehow contains the time. And yet time refuses to be bottled up like a genie stuffed in a lamp. Whether it flows as sand or turns on wheels within wheels, time escapes irretrievably, while we watch...when the mainspring winds down so far that the clock hands hold still as death, time itself keeps on. The most we can hope a watch to do is to mark that progress. And since time sets its own tempo, like a heartbeat or an ebb tide, timepieces don't really keep time. They just keep up with it, if they're able."

"With is marine clocks, John Harrison tested the waters of space-time. He succeeded, against all odds, in using the fourth - temporal - dimension to link points on the three-dimensional globe. He wrested the world's whereabouts from the stars, and locked the secret in a pocket watch."

Sobel is a good storyteller. Her description, at the beginning of the final chapter, of standing on the prime meridian of the world and how it is lit up these days in Greenwich, at the Old Royal Observatory, makes me want to see it for myself. ( )

This is the story of the development of a clock accurate enough to measure longitude while at sea. As someone who was almost completely ignorant of pre-GPS maritime navigation techniques, this was fascinating to me. I'd never given much thought to how one finds their location on the ocean where there are no landmarks save the heavens. The descriptions of the clocks were marvelous; now I want to run off to Greenwich to see them. Though maritime adventure stories don't interest me, the history of maritime technology certainly does. The difficulties faced at sea are so different from those on land, and the ingenious methods of overcoming them make for good reading.

A note on the audio: Kate Reading is not my favorite narrator. Her stilted cadence has ruined more than one audiobook for me, to the point where I avoid listening to books she reads. However, I decided to give this nonfiction a chance, and it wasn't too bad. I think a lot of the problem in other books is her atrocious attempt at an American accent. Using her natural British accent here, it sounded much more natural. It also helped that there wasn't much in the way of dialogue. ( )

Sobel has told a complex story very clearly, staying with the toplc closely and without straying into related events and issues - although she does include many fascinating snippets from history. It is focused on the central character of John Harrison and his achievement of inventing a chronometer that would determine longitude. Her admiration is clear. I pitied Harrison, who spent his life on the job yet parliamentarians were reluctant to award the £20,000 Longitude prize. Thanks to Sobel's writing ability, this short book is a wonderful story, skillfully told. ( )

Ms. Sobel, a former science reporter for The New York Times, confesses in her source notes that ''for a few months at the outset, I maintained the insane idea that I could write this book without traveling to England and seeing the timekeepers firsthand.'' Eventually she did visit the National Maritime Museum in Greenwich, where the four clocks that James Harrison constructed are exhibited.She writes, ''Coming face with these machines at last -- after having read countless accounts of their construction and trial, after having seen every detail of their insides and outsides in still and moving pictures -- reduced me to tears.''Such is the eloquence of this gem of a book that it makes you understand exactly how she felt.

Here's a swell little book that tells an amazing story that is largely forgotten today but that deserves to be remembered.

It is the story of the problem of navigation at sea--which plagued ocean-going mariners for centuries--and how it was finally solved.

It is the story of how an unknown, uneducated and unheralded clockmaker solved the problem that had stumped some of the greatest scientific minds. And it is the story of how the Establishment of the 18th Century tried to block his solution.

The essential problem is this: In the middle of the ocean, how can you tell where you are? That is, how can you tell how far east or west of your starting point you have gone?

The history of portable time, or watch, and its important impact on navigating waters. John Harrison’s inventions of timepieces (H-1, H-2, H-3) leading up to the chronometer (H-4) in 1760 and its ability to chart longitude. John Harrison’s difficulties with the Board of Longitude in acknowledging his masterpiece.

The thorniest scientific problem of the eighteenth century was how to determine longitude. Many thousands of lives had been lost at sea over the centuries due to the inability to determine an east-west position. This is the engrossing story of the clockmaker, John "Longitude" Harrison, who solved the problem that Newton and Galileo had failed to conquer, yet claimed only half the promised rich reward.

During the great age of exploration, the "longitude problem" was the gravest of scientific challenges. Without the ability to determine longitude, sailors and their ships were lost at sea as soon as they lost sight of land. In 1714, desperate for a solution, England's Parliament offered 20,000 pounds (the equivalent of millions of dollars today) to anyone who could solve the problem. With all the skill and storytelling ability of a great novelist, Dava Sobel captures the dramatic story at the heart of this epic scientific quest.… (more)